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The integration of solar‐driven interfacial evaporation and electricity co‐generation is considered a promising approach to simultaneously alleviate freshwater scarcity and the energy crisis. However, affected by intermittent solar irradiation/uncontrollable weather, the overall performance of solar‐driven evaporation in the real world is greatly reduced. Herein, inspired by antifreeze proteins in beetles that survive in extreme climates, all‐weather solar‐driven interfacial evaporators with a sandwich structure are designed. The top and bottom layers composed of MnO2‐modified cotton cloth are used for photothermal conversion and water transport, meanwhile, the middle layer made of a phase change microcapsule/hydrogel composite serves for heat storage and release. Under 1 kW m−2 irradiation, the evaporator exhibits a high evaporation rate of 2.67 kg m−2 h−1 and an efficiency of 89.5%. In the dark, the heat released from the phase change layer supports an evaporation rate of 0.43 kg m−2 h−1, 3.6 times that of pure water. Additionally, assembled with a thermoelectric module, the hybrid device achieves a stable output electricity power of 0.42 W m−2 under 1‐sun illumination and a prolonged output for 30 min in the dark. This work provides a novel approach for full‐time solar‐powered steam‐electricity co‐generation and a proof of concept for biomimetic steam generation/heat management integration. [ABSTRACT FROM AUTHOR]

Upcycling waste plastics into advanced semiconductor photocatalysts provides a new strategy to reasonably and economically solve the huge amount of waste plastics, which remains challenging. Herein, a carbon nitride‐based donor–acceptor (D–A) conjugated copolymer by copolymerization of dicyandiamide and terephthalic acid from discarded polyethylene terephthalate (PET) using Zn(OH)2 as catalyst and template at 360–440 °C is synthesized. The morphology and structure of the conjugated copolymer are well regulated by the calcination temperature. The resultant conjugated copolymer exhibits merits of high light absorption and low electron–hole recombination probability. Consequently, it works excellently in the persulfate‐based advanced oxidation process for visible light‐driven photocatalytic degradation of tetracycline. The kinetic constant (3.4 × 10−2 min−1) is 40.5 and 2.3 times that of the conjugated copolymer system and persulfate system, respectively. Furthermore, the reactive species (including •OH, SO4•−, •O2−, 1O2, and h+) and degradation intermediates of tetracycline are analyzed to expound its degradation process. This work not only pioneers design guidelines on upcycling of waste plastics in a sustainable manner, but also provides a facile strategy to synthesize carbon nitride‐based D–A conjugated copolymers for the efficient activation of persulfate‐based advanced oxidation process in wastewater treatment. [ABSTRACT FROM AUTHOR]

Owing to the surge of energy storage devices, lithium and beyond‐lithium metal ion batteries (MIBs) have gained considerable research attention. The large size and multivalent ions drastically deteriorate the performance of conventional battery electrode materials which demands unique types of structures in order to fulfill the electrode requirements of next‐generation MIBs. Developing atomically thin nanosheets confined in 2D heterostructures is a favorable choice to synergistically handle the deficiencies of individual 2D materials and achieve distinct physical and electrochemical properties, retaining their 2D features. This article sheds light on the significance and characteristics of graphene‐based and beyond‐graphene 2D heterostructures as electrode materials in lithium‐ion, sodium‐ion, potassium‐ion, magnesium‐ion, and aluminum‐ion batteries. In this regard, the pathways for the selection of 2D heterostructures electrode materials and their possible geometric configurations are first recognized. Second, the fundamental science, underlying charge storage mechanisms, and robust interfacial charge transfer processes in 2D heterostructures are discussed comprehensively in the context of recent computational studies. Third, the recent state‐of‐the‐art experimental approaches for the fabrication of novel 2D heterostructures and their performance as anode and cathode materials for MIBs are discussed systematically. Finally, the current challenges facing 2D heterostructures and potential future research directions in the context of advanced MIBs are highlighted. [ABSTRACT FROM AUTHOR]

Due to the ever-increasing plastic waste causing serious environmental problems, it is highly desirable to recycle it into high-value-added products, such as carbon nanomaterials. However, the traditional catalytic carbonization of hydrocarbon polymers is severely prohibited by the complexity of real-world plastic waste due to the existence of halogen-containing polymers. In this study, through a universal combined template based on magnesium oxide and iron(III) acetylacetonate (Fe(acac)3), a three-dimensional hollow carbon sphere/porous carbon flake hybrid nanostructure is prepared from carbonization of plastic waste with high yields (>70 wt%). This approach is not only suitable for hydrocarbon polymers, but also for halogen-containing polymers. Interestingly, the obtained advanced carbon framework exhibits excellent performance in lithium-ion batteries (802 mA h g−1 after 500 cycles at 0.5 A g−1). The present research paves a new avenue to upcycle plastic waste into a high value-added product. [ABSTRACT FROM AUTHOR]

Solar steam generation is emerging as a promising technology to harvest solar energy for diverse applications such as distillation, desalination, and production of freshwater. However, the synthesis of low-cost and high-efficiency photothermal materials remains a challenge for both industrial and academic research. Here, hierarchically porous carbon having an irregular, inter-connected nanoparticle morphology is facilely synthesized through "controlled carbonization" of low-cost waste poly(ethylene terephthalate) (PET) using ZnCl2/NaCl eutectic salts at 550 °C. We prove that ZnCl2 catalyzes the dehydration and decarboxylation of PET to form vinyl-terminated chain fragments and aromatic rings, which subsequently construct a carbon material frame through further cyclization and crosslinking. Meanwhile ZnCl2/NaCl eutectic salts act as porogens to produce mesopores and macropores. The resultant hierarchically porous carbon shows high specific surface area, fast water transportation, high solar absorption efficiency, and low thermal conductivity. Such combined features endow it with a high evaporation rate of 1.68 kg m−2 h−1 under 1 sun irradiation, an energy conversion efficiency of 97%, and a metallic ion removal efficiency of ca. 99.9% for seawater. More importantly, it outperforms the state-of-the-art carbon-based photothermal materials. This work not only reveals the potential of hierarchically porous carbon for application in solar steam generation, but also gives impetus to the sustainable conversion of low-cost waste polyesters into valuable carbon materials by a "controlled carbonization" strategy for energy storage and conversion, environmental remediation, etc. [ABSTRACT FROM AUTHOR]

A facile and efficient method is used to synthesize porous iron oxide coated with graphene as electrode materials for lithium-ion batteries and supercapacitors. Graphene encapsulation of porous Fe2O3 and Fe3O4 nanorods is directly carried out from FeOOH@GO colloids by taking advantage of an electrostatic self-assembly method, owing to the positively-charged surface of FeOOH and the negatively-charged surface of GO. The combination of graphene and porous iron oxide brings about multifunctional features of the electrode materials as follows: (1) enhanced electrical conductivity makes the electrodes the current collectors; (2) reinforced softness of the electrodes accommodates the large volume changes during charge–discharge cycles; (3) improved high specific surface area of the electrodes increases the accessibility of the active electrode materials to electrolyte; (4) the pores formed by graphene and iron oxide particles facilitate ion transportation; (5) iron oxide particles separate graphene and prevent their restacking or agglomeration, and vice versa, thus improving the immersion and splitting of electrolyte into and out of the electroactive material. Consequently, the porous iron oxide/graphene hybrid nanocomposites deliver a good performance in the electrochemical energy storage for lithium-ion batteries and supercapacitors. [ABSTRACT FROM AUTHOR]

Poly(butylene succinate)/magnesium hydroxide (PBS/Mg(OH)2) composites were prepared by melt compounding to investigate the effect of particle size on the flame retardancy of PBS. Their flammability properties were investigated by limiting oxygen index, UL-94, and cone calorimeter tests, which suggested that the medium-sized Mg(OH)2-5 µm displayed the best flame retardancy. The residual char structure were analyzed and indicated that Mg(OH)2-5 µm could form a better protective layer than other sized particles, leading to the better flame retardancy to PBS. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Core–shell hybrid particles, possessing a hard core of silica particles (SiPs) and a soft shell of brushlike polystyrene (PS), were successfully prepared by the combination of lithium–iodine exchange (LIE) and surface-initiated living anionic polymerization (SI-LAP). The molecular weight, graft density and brush thicknesses of the PS brushes were controllable. [ABSTRACT FROM AUTHOR]

Converting waste plastics into valuable carbon materials has obtained increasing attention. In addition, carbon materials have shown to be the ideal electrode materials for double‐layer supercapacitors owing to their large specific surface area, high electrical conductivity, and stable physicochemical properties. Herein, an easily operated approach is established to efficiently convert waste poly(ethylene terephthalate) beverage bottles into porous carbon nanosheet (PCNS) through the combined processes of catalytic carbonization and KOH activation. PCNS features an ultrahigh specific surface area (2236 m2 g−1), hierarchically porous architecture, and a large pore volume (3.0 cm3 g−1). Such excellent physicochemical properties conjointly contribute to the outstanding supercapacitive performance: 169 F g−1 (6 M KOH) and 135 F g−1 (1 M Na2SO4). Furthermore, PCNS shows a high capacitance of 121 F g−1 and a corresponding energy density of 30.6 Wh kg−1 at 0.2 A g−1 in the electrolyte of 1 M TEATFB/PC. When the current density increases to 10 A g−1, the capacitance remains at 95 F g−1, indicating the extraordinary rate capability. This work not only proposes a facile approach to synthesize PCNS for supercapacitors, but also puts forward a potential sustainable way to recycle waste plastics and further hopefully mitigates the waste plastics‐related environmental issues. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48338. [ABSTRACT FROM AUTHOR]

The derived lysine from biomass fermentation is a naturally abundant renewable resource. However, the small molecular size of lysine limits its processing and application. On the other side, carbonization of polylysine into high‐valued carbon materials is one of convenient options to apply for energy storage devices. Herein, we prepare polylysine@silica hybrid nanostructure through thermal polymerization of lysine and biosilicification of tetraethoxysilane (TEOS). Subsequently, nitrogen‐containing porous carbon flakes (NPCF) are synthesized upon carbonization. Interestingly, the synthesized NPCF presents hierarchical porous framework structure with interconnected micro‐meso‐macro pores. Consequently, the NPCF delivers an excellent supercapacitor performance. For instance, our characterizations display specific capacitance up to 242 F/g at 1 mV/s and 186 F/g at 1 A/g, and could keep 96.3% initial capacity after 10,000 cycles at 10 A/g. These achievements are because of hierarchical porosity, proper nitrogen content, and accessible surface area of nanostructured NPCF. Therefore, our work creates a novel and sustainable route for fabricating NPCF with promising applications in the supercapacitors. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48214. [ABSTRACT FROM AUTHOR]

With the purpose to turn wastes into wealth and develop renewable energy, much effort has been focused on converting biowastes into porous carbons and exploring their application for supercapacitors. In this study, inspired by natural porous structure of biomass and small size of Sn nanoparticles, a one-step strategy was developed to convert waste wolfberry fruits into porous carbons by SnCl 2. The as-fabricated carbon exhibited large specific surface area of 1423 m2 g−1 and hierarchical porosity with total pore volume of 1.36 cm3 g−1. Meanwhile, the newly produced SnCl 2 with more than 95% recovery rate was reused as catalyst. Moreover, the porous carbon was applied for supercapacitive electrode. In three-electrode 6 M KOH system, it displayed outstanding capacitance of 365 F/g at 0.2 A g−1, good rate capability of 75% capacitance retention at 20 A g−1 and excellent cycling stability of 96.4% capacitance retention after 10000 cycles. In two-electrode 1 M Li 2 SO 4 system, its energy density reached 23.2 Wh kg−1 at a power density of 225 W kg−1. The current work provided a facile and low-cost method to recycle renewable biowastes into high-valued carbon material, and further expanded its application for high-performance energy storage devices. [Display omitted] [ABSTRACT FROM AUTHOR]

Polystyrene (PS) is usually discarded as a solid waste after a short lifespan. Thus the disposal of waste PS is an inevitably worldwide issue because of their stable and non-biodegradable nature. Herein, a facile method was proposed to carbonize PS waste into novel three-dimensional (3D) hierarchically porous carbon using Fe 2 O 3 particles as both catalyst and template. Furthermore, KOH activation was applied to generate microporous and mesopores on the wall of macropores. As a result, the obtained 3D hierarchically porous carbon exhibits a high specific capacitance of 284.1 F g -1 at 0.5 A g -1 and good rate performance of 198 F g -1 at 20 A g -1 in a three-electrode device. Moreover, the assembled symmetrical capacitor displays a high energy density of 19.2 W h kg -1 at the power density of 200.7 W kg -1 in aqueous electrolyte. Therefore, the present research develops a sustainable way to recycle waste plastics into 3D hierarchically porous carbon for supercapacitors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Herein, polystyrene waste was carbonized into mesoporous carbon nanosheets (CNS) using the template method. The pore structure of the obtained CNS was further tuned by KOH activation, resulting in the formation of hierarchical porous carbon sheets with a specific surface area of 2650 m 2 g -1 and a pore volume of 2.43 cm 3 g -1 . Benefiting from these unique properties, in a three electrode system, the hierarchical porous carbon sheets displayed a specific capacitance of 323 F g -1 at 0.5 A g -1 in a 6 M KOH electrolyte, good rate capability (222 F g -1 at 20 A g -1 ) and cycle stability (92.6% of capacitance retention after 10 000 cycles). More importantly, an energy density of 44.1 Wh kg -1 was also displayed with a power density of 757.1 W kg -1 in an organic electrolyte. In this regard, the present strategy demonstrates a facile approach for recycling plastic waste into high value-added products, which will potentially pave the way for the treatment of plastic waste in the future.

Although many biosilicification methods based on cationic linear α-poly -l- lysine for synthesis of polylysine/silica hybrids have been investigated, these methods tend to rely on the counteranions, added catalysts, and complex synthesis process. To explore a simple and efficient biosilicification method, in this work, branched poly-l-lysine (BPL) is used as both a catalyst to hydrolyze tetraethoxysilane (TEOS) and an in situ template to direct silicic acids forming polylysine/silica hybrids in one-pot mode. The catalysis of BPL to hydrolyze TEOS results from the abundant hydrogen bonding (as the active site) to increase the nucleophilicity of BPL. Meanwhile, the hydrogen bonding is also found to be the key factor determining the self-assembly of BPL. During biosilicification, owing to self-assembly of BPL molecules, BPL would form spherical particles by keeping a random-coil conformation or form lamellar structures by undergoing a conformational transition from a random-coil to β-sheet construction. As a result, polylysine/silica hybrids with tunable topological structures are synthesized using aggregated BPLs as templates after the hydrolysis of TEOS. This finding of applying BPL to fulfill the biosilicification procedure without counteranions and added catalysts would enable a better understanding of the polypeptide-governed biosilicification process and pave a way for fabricating complex inorganic architectures applicable to silica transformational chemistry., Competing Interests: The authors declare no competing financial interest.